Anyone had the red battery warning indicator show?

[highsider]

I was trying to charge the car at a public charger last week, and it wouldn't connect to start charging. I noticed the driver display was showing a red battery indicator. Looking at the manual, it said it was a Low-voltage Battery Charging System Malfunction Warning Lamp.

I locked the car and left it for a while. Returning to the car later, the indicator doesn't show and the car started to charge fine.

I was going to contact the dealer, but it seems to rectify itself.

Anyone else experience this?

 

[Rolfe]

I may have seen it. I thought it was doing what ICE cars do and showing that when you're getting ready to start moving.

 

[tsedge]

It could be a glitch or a problem with a discharged 12V battery. What does it report the 12V battery voltage to be?

If you've only seen this once, I suspect and glitch.

 

[elias]

Hi, I just saw the same warning light on my car today. I was driving during the weekend and left the car in the garage, connected to the charger with a schedule to slowly charge from my solar system at home (13:00 to 16:30).

It charged just fine yesterday, but today, when I got in to setup the charge current at 6A (cloudy day), I got the error message. As soon as the car restarted the charge (it always stops charging when you open the door), the error icon went off and the battery voltage showed 14.1V, so it is clearly charging. I'll check actual voltage with a multimeter tonight, after the current schedule finishes, and report back.

I'm inclined to think this is just another of those glitches, like the low temperature warning I get from time to time, even though ambient temperature has been over 25 °C from the moment I bought the car back in July.

Update: I didn't check actual voltage with the multimeter, but I've verified that, after the charge schedule finished, the low voltage battery was sitting at 12.7V (fully charged) and went up to 14V a bit after I powered the car on. The battery warning light didn't came up this time.

 

[MarcS]

I had the same problem today, not able to charge and the red battery sign was on, however the voltage was 14.1V.
Tried later again and all was oké again.
Trophy R46 phase1

 

[Martinonline]

I had this on Sunday. I reported in the thread '12v battery charging'. It may be linked to the colder weather. Since Sunday I have not had a problem but I am monitoring the voltage.

 

[PristDean]

As the 12v is susceptible to discharging (and not being topped up by the HV battery) if:
1. A charger is connected but not charging the car
2. The HV battery is lower than 20% charge
3. Weather temperature changes
4. The above coupled with App interrogations of the car

I have installed the below and find its very useful. It will notify you of a low battery condition and you can set how low etc. However, be careful installing as the MG4 has a support bar running across the middle of the battery, so waving spanners around in that area is just asking for a new hair style !

BM2 Battery Monitor

 

[Rolfe]

If it's reading low, though, what do you do about it?

 

[AndyL61]

If it's reading low, though, what do you do about it?

It would give you a chance to charge or even replace the battery before it's so low that the car won't operate.

 

[Rolfe]

My current thought is, get a battery booster pack and carry it. If it starts you that quickly, then you're scarcely delayed. If it happens repeatedly, then replace the battery or investigate why it isn't charging up.

 

[elias]

I'm starting to consider replacing the lead acid battery by one of those compatible 12V lithium batteries. They have the same form factor and integrate a charger inside, so it should be plug and play solution.

 

[Rolfe]

There has been some discussion about that on one of the other 12v battery threads. Probably this one.

12v battery and Noco booster

Has anyone had to use this booster or any other in anger and did it work as expected? We all think we know the theory of how to use them on a EV but does that match the actuality. Scenario, you get back to the car and its dead, you had the foresight to buy said item, so dismantle the key ring...

www.mgevs.com

 

[dsimpkins]

I had the same problem today, not able to charge and the red battery sign was on, however the voltage was 14.1V.
Tried later again and all was oké again.
Trophy R46 phase1

If the 12v battery was at 14.1v it means it was being charged from the HV battery. You would get a similar reading from an ICE car with the engine running, and the alternator charging the battery.

It would suggest that you cannot charge the HV battery if the 12V battery is low.

 

[Evgen K]

I saw the same warning "Low-voltage Battery Charging System Malfunction Warning" indicator at top right corner together with "Power Battery Cut-off" indicator warning at left bottom corner of driver screen twice:

In both cases it was after charging the car by quick charger from ~18% to 90-95% (car was charged for long range trip). Putting the car into ready cleared both of these faults on the driver’s screen.

Does it mean that 12v battery is almost dead and should have been replaced?

 

[ZiggyStandard]

I saw the same warning "Low-voltage Battery Charging System Malfunction Warning" indicator at top right corner together with "Power Battery Cut-off" indicator warning at left bottom corner of driver screen twice:
View attachment 29560View attachment 29561
In both cases it was after charging the car by quick charger from ~18% to 90-95% (car was charged for long range trip). Putting the car into ready cleared both of these faults on the driver’s screen.

Does it mean that 12v battery is almost dead and should have been replaced?

Did your battery need replacing?

 

[Martinonline]

@Evgen K, if the main battery is disconnected then it cannot charge the 12v battery so I assume the two warnings will show together if the main battery is disconnected. I also have seen the power battery cut-off warning after ultra-rapid charging. I had just the 12v low battery warning last year but no problems since.

 

[Evgen K]

@Evgen K, if the main battery is disconnected then it cannot charge the 12v battery so I assume the two warnings will show together if the main battery is disconnected. I also have seen the power battery cut-off warning after ultra-rapid charging. I had just the 12v low battery warning last year but no problems since.

Thanks. Yes it was rapid charging with 140 kW power ~30 mins. It's strange that 12v battery drained during this time.

 

[Evgen K]

Did your battery need replacing?

Maybe, i didn't visited service yet. Currently it works ok, but i think the main battery just charge 12V battery when it drained.